Telegram’s approach is more confusing. By default, there is no E2EE on Telegram private or group messages. These are encrypted server side, which means that, in theory, the company can decrypt their content if it wants to. Telegram private chats offer E2EE, but it’s inconvenient to set up. Durov has blogged on why the company eschews E2EE, mainly, he claimed, so that users can conveniently back up and access messages across multiple devices. 

That’s the main reason why it makes sense for police to target criminals on the platform in a way that’s impossible with apps using E2EE: Telegram should be able to unscramble the content of Telegram messages if it chooses to.

Of course, as an app which has long played on its unruly MO, Telegram doesn’t want to advertise that uncomfortable possibility. Indeed, the company has long talked up its willingness to resist government oversight, including falling out with Russia’s Federal Security Service (FSB) in 2018 over its refusal to grant access to communications.